3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php $a = ""; $a[] = 42; var_dump($a);
based on LZU0E
Output for 7.1.0
Fatal error: Uncaught Error: [] operator not supported for strings in /in/9dpbU:2 Stack trace: #0 {main} thrown in /in/9dpbU on line 2
Process exited with code 255.
Output for 4.3.0 - 7.0.14
array(1) { [0]=> int(42) }